1. Field of the Invention
The present invention relates to friction clutch for a transmission of a motor vehicle and also to a clutch plate for a friction clutch. More specifically, the present invention relates to a torsional vibration damper in a clutch plate in the drive train of a motor vehicle. Such a torsional vibration damper in the drive train of a motor vehicle can typically have a disc-shaped input part with friction linings that can be arranged concentric to an axis of rotation, and a disc-shaped output part, which can likewise be oriented concentric to the axis of rotation.
The disc-shaped output part can also have a hub so that the output part can be non-rotationally mounted on a gear shaft. Such a torsional vibration damper can also have springs disposed in apertures of the input part and the output part, for the transmission of torque from one part to the other, against the force of the spring as the two parts rotate relative to one another. In addition, a friction ring arrangement can be disposed between axially opposite surfaces of the input part and the output part. This friction ring arrangement can have a friction ring to which an axial force is applied, which friction ring can be installed concentric to the axis of rotation.
2. Background Information
German Patent Specification 916 016, for example, discloses one known type of torsional vibration damper in a clutch plate which is similar to the design mentioned above. For the damping of torsional vibrations on this known clutch plate, there are both torsion springs in the form of coil springs and a system of friction rings between axially opposite surfaces of the input part and the output part, to which surfaces an axial force is applied. The friction effect is produced by means of either axially zig-zag and installed metal spring elements or a system of friction rings consisting of such spring elements together with loosely inserted friction rings.
On the one hand, a metal-on-metal frictional force is generated in this case, which causes problems of coordinating the achievable frictional force with the level of the frictional force and the evenness of the frictional force. On the other hand, separate rings manufactured from different materials and thus having different coefficients of friction are inserted loosely into the system, whereby no specific friction surface is defined. The friction surface can easily change during operation, whereby uncontrolled fluctuations in the generation of frictional force cannot be avoided.